The Holcim Group plans to capture CO2 emissions from cement production and store them underground. The Swiss corporation is betting on Carbon Capture and Storage (CCS), a technology that remains controversial in climate debates. While supporters view CCS as an indispensable component for decarbonizing energy-intensive industries, critics warn that it is a greenwashing instrument that legitimizes climate-damaging production processes.
Why the cement industry faces a decarbonization problem
Cement production is one of the most emissions-intensive industrial processes worldwide. Approximately eight percent of global CO2 emissions come from cement production. The majority of these emissions – roughly two-thirds – do not result from energy consumption but occur process-conditionally during the thermal decomposition of limestone into clinker, the main component of cement. This chemical reaction is physically unavoidable and cannot be eliminated through efficiency improvements or renewable energy alone.
CCS addresses precisely this point: The technology is designed to capture CO2 directly at its source before it enters the atmosphere. The captured CO2 is then compressed and permanently stored in geological formations. For the cement industry, CCS could theoretically address emissions resulting from process heat and chemical reactions – a potential that other decarbonization approaches do not offer.
Technological hurdles and infrastructure requirements
The practical implementation of CCS in cement production is technically demanding. First, CO2 must be separated from the exhaust stream, which requires different methods – ranging from amine scrubbing to membrane technologies to oxyfuel processes, in which combustion occurs under oxygen rather than air. Each of these technologies is energy-intensive and significantly increases the electricity demands of production.
After capture, the CO2 must be compressed, transported, and stored. This requires extensive pipeline infrastructure and suitable geological storage formations. In Germany, such storage sites are limited and politically controversial. Public acceptance for underground CO2 storage is low in many regions, which can delay or prevent approval procedures.
There is also the question of long-term safety: CO2 must remain securely confined for centuries. Leaks could not only be counterproductive from a climate policy perspective but also pose risks to groundwater and ecosystems. Monitoring and liability for such long-term risks have not yet been fully clarified regulatory.
Cost efficiency and competitiveness
The costs of CCS applications in the cement industry are considerable. Estimates range from an additional 60 to 120 euros per ton of avoided CO2 – depending on the technology used, facility size, and transport distances. With an average CO2 intensity of around 600 kilograms per ton of cement, CCS would increase production costs by at least 36 euros per ton, corresponding to a cost increase of 30 to 50 percent.
These additional costs can only be recouped through higher sales prices, which is problematic in a highly competitive market. Without supporting measures such as CO2 border adjustment mechanisms or government subsidies, manufacturers investing in CCS risk a competitive disadvantage compared to suppliers from regions with less stringent climate requirements.
Holcim is not the only cement manufacturer exploring CCS. Heidelberg Materials and CEMEX have also announced pilot projects. The race for climate-neutral cement is increasingly being decided by technological leadership roles and regulatory frameworks.
Alternative decarbonization strategies: Clinker substitution and hydrogen
CCS is not the only option for reducing emissions in cement production. A more cost-effective alternative is the substitution of clinker with alternative binders such as blast furnace slag, fly ash, or calcined clays. These materials can replace up to 50 percent of clinker, correspondingly reducing process-related CO2 emissions. The use of such supplementary materials is technically proven and regulated in standards such as DIN EN 197-1.
However, the availability of alternative binders is limited. Blast furnace slag is a byproduct of steel production, whose volume is declining. Fly ash comes from coal power plants, which are being shut down as part of the energy transition. Calcined clays are a promising alternative but also require energy-intensive processes and are not yet available on an industrial scale.
Another approach is the use of hydrogen or biomass to fuel cement kilns. This would eliminate energy-related emissions but not process-related CO2 releases from calcination. Hydrogen is currently expensive and only limitedly available in green form. The transition requires extensive modifications to kiln technology.
In practice, a combination of several strategies will be required: clinker substitution to reduce process-related emissions, electrification or hydrogen for process heat, and CCS for remaining unavoidable emissions. No single approach can solve the cement industry's decarbonization problem alone.
Regulatory framework and EU climate goals
The European Union has formulated ambitious climate goals with the Green Deal and the Fit-for-55 package. By 2030, greenhouse gas emissions should be reduced by at least 55 percent compared to 1990, and climate neutrality should be achieved by 2050. The cement industry faces increasing pressure to contribute to these goals.
The EU Emissions Trading System (EU ETS) is gradually increasing the CO2 price and reducing free allocation of emission certificates. Starting in 2026, the CO2 Border Adjustment Mechanism (CBAM) will also levy a CO2 surcharge on imports from third countries to prevent carbon leakage. These regulations create economic incentives for investments in low-emission technologies – but also pose risks for companies that do not transform in time.
At the same time, the EU promotes decarbonization projects through programs such as the Innovation Fund, which also supports CCS initiatives. Germany passed a CCS law in 2024 that permits underground CO2 storage under strict conditions. Whether these framework conditions are sufficient to establish CCS broadly remains to be seen.
Holcim's strategy in the context of industry dynamics
Holcim's announcement of investment in CCS is part of a more comprehensive decarbonization strategy. The company has set the goal of reducing CO2 emissions by 30 percent by 2030 and achieving climate-neutral production by 2050. CCS is to be understood as a complementary technology that supplements clinker substitution, energy efficiency, and alternative fuels.
Specific implementation details – such as locations, timelines, investment volumes, or storage capacities – were not mentioned in the announcement. This is typical for early project phases but makes a reliable assessment of feasibility difficult. Critics accuse the company of signaling climate protection ambitions through such announcements without committing to binding measures.
Industry observers point out that CCS projects in the cement industry are still predominantly in pilot stages. Scaled, commercial application is yet to come. Whether Holcim can take a leadership role here or whether the project will fail at technical, economic, or political hurdles will be decided in the coming years.
Conclusion: CCS as a necessary building block or delaying tactic?
Carbon Capture and Storage can be an important building block for decarbonizing the cement industry – particularly for unavoidable process-related emissions. However, the technology is not a solution on its own. High costs, lack of infrastructure, regulatory uncertainties, and social acceptance problems present considerable hurdles.
At the same time, CCS must not serve as an excuse to delay necessary measures for clinker substitution, energy efficiency, and circular economy practices. The most promising strategy combines multiple approaches: maximum clinker reduction through alternative binders, electrification or hydrogen for process heat, and CCS for remaining residual emissions.
Whether Holcim's CCS initiative actually contributes to climate neutrality or is a delaying tactic will become evident through concrete implementation steps, investment commitments, and measurable emission reductions. The coming years will be decisive – for the company, the industry, and the achievement of climate goals.
